Robusta coffee fell to the lowest level in more than nine months as bean exports from Vietnam, the world's largest producer of the variety used in instant coffee and espresso, continued to rise. Cocoa declined.

Vietnam may export 122,000 metric tons of coffee this month, according to an estimate from the Ministry of Agriculture and Rural Development. That is up from an estimate of 79,000 tons last month. The Southeast Asian nation may produce 26 million bags this year, little changed from 27 million bags a year earlier, Rabobank International said. A bag of coffee usually weighs 60 kilograms (132 pounds).

"Selling from Vietnam and increased expectations for the crop has led to a more bearish outlook from investors," Keith Flury, a senior commodities analyst at Rabobank in London, said by e-mail Tuesday. "The trade seems to be well-covered."

Robusta coffee for January delivery slid 1 percent to $1,840 a ton by 10:36 a.m. on NYSE Liffe in London. The price touched $1,836 a ton, the lowest since Feb. 7. Arabica coffee for March delivery was down 1.4 percent to $1.487 a pound on ICE Futures US in New York, after touching $1.478, the lowest since June 14, 2010.

Arabica coffee, favored for specialty drinks such as those made by Starbucks Corp., as the dollar gained against the Brazilian real this month, boosting the incentive to sell.

"It is very likely that the appreciating U.S. currency resulted in an increase in selling, adding pressure to the market," Flury said.

White, or refined, sugar for March delivery was little changed at $510.10 a ton on NYSE Liffe. Raw sugar for March delivery gained 0.4 percent to 19.21 cents a pound on ICE.

Cocoa for March delivery was down 0.6 percent to 1,588 pounds ($2,544) a ton in London. Cocoa for March delivery fell 0.7 percent to $2,496 a ton in New York.